DISPLACEMENT MEASUREMENT METHOD OF ISOCENTER IN RADIOTHERAPY APPARATUS, ADJUSTMENT METHOD OF DISPLACEMENT OF THE SAME, AND PHANTOM FOR DISPLACEMENT MEASUREMENT

摘要

PROBLEM TO BE SOLVED: To provide a measurement method for measuring displacement (deviation) of an isocenter of treatment X-rays, a virtual isocenter by a laser beam for position determination, and a center position irradiated with diagnosis X-rays from a diagnosis X-ray photography device in a radiotherapy apparatus, an adjustment method for adjusting the displacement, and to provide a phantom for displacement measurement used in the measurement method and the adjustment method.;SOLUTION: The measurement method executes, in an arbitrary order, a step of measuring the displacement of the position of an actual isocenter 71 by the treatment X-rays and the position of an X-ray absorber disposed at a virtual isocenter from irradiation image information obtained by irradiating the X-ray absorber embedded inside the phantom 10 with the treatment X-rays for the displacement measurement from a gantry 41 of the radiotherapy apparatus 4, and a step of measuring the displacement of the center position of the diagnosis X-rays and the position of the X-ray absorber disposed at the virtual isocenter from irradiation image information obtained by irradiating the X-ray absorber with the diagnosis X-rays from the diagnosis X-ray photography device 44.;COPYRIGHT: (C)2013,JPO&INPIT